首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   12659篇
  免费   308篇
  国内免费   328篇
耳鼻咽喉   153篇
儿科学   123篇
妇产科学   221篇
基础医学   1085篇
口腔科学   213篇
临床医学   1045篇
内科学   2320篇
皮肤病学   171篇
神经病学   1587篇
特种医学   406篇
外科学   822篇
综合类   735篇
现状与发展   1篇
一般理论   4篇
预防医学   870篇
眼科学   405篇
药学   1866篇
  18篇
中国医学   684篇
肿瘤学   566篇
  2023年   334篇
  2022年   788篇
  2021年   1162篇
  2020年   1224篇
  2019年   1420篇
  2018年   1332篇
  2017年   949篇
  2016年   697篇
  2015年   370篇
  2014年   679篇
  2013年   1447篇
  2012年   1289篇
  2011年   345篇
  2010年   242篇
  2009年   131篇
  2008年   117篇
  2007年   86篇
  2006年   64篇
  2005年   73篇
  2004年   60篇
  2003年   68篇
  2002年   46篇
  2001年   19篇
  2000年   22篇
  1999年   13篇
  1998年   10篇
  1996年   18篇
  1995年   19篇
  1994年   19篇
  1993年   13篇
  1992年   6篇
  1991年   10篇
  1990年   10篇
  1989年   3篇
  1988年   4篇
  1987年   4篇
  1986年   6篇
  1985年   42篇
  1984年   20篇
  1983年   24篇
  1982年   25篇
  1981年   21篇
  1980年   11篇
  1979年   11篇
  1978年   13篇
  1977年   6篇
  1976年   5篇
  1975年   9篇
  1974年   6篇
  1973年   2篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
《Clinical neurophysiology》2021,132(10):2357-2364
ObjectivesTo investigate the subcortical somatosensory evoked potentials (SEPs) to electrical stimulation of either muscle or cutaneous afferents.MethodsSEPs were recorded in 6 patients suffering from Parkinson’s disease (PD) who underwent electrode implantation in the pedunculopontine (PPTg) nucleus area. We compared SEPs recorded from the scalp and from the intracranial electrode contacts to electrical stimuli applied to: 1) median nerve at the wrist, 2) abductor pollicis brevis motor point, and 3) distal phalanx of the thumb. Also the high-frequency oscillations (HFOs) were analysed.ResultsAfter median nerve and pure cutaneous (distant phalanx of the thumb) stimulation, a P1-N1 complex was recorded by the intracranial lead, while the scalp electrodes recorded the short-latency far-field responses (P14 and N18). On the contrary, motor point stimulation did not evoke any low-frequency component in the PPTg traces, nor the N18 potential on the scalp. HFOs were recorded to stimulation of all modalities by the PPTg electrode contacts.ConclusionsStimulus processing within the cuneate nucleus depends on modality, since only the cutaneous input activates the complex intranuclear network possibly generating the scalp N18 potential.SignificanceOur results shed light on the subcortical processing of the somatosensory input of different modalities.  相似文献   
2.
3.
AimThe aim of the study was to describe the characteristics of the Bachelor’s thesis of fourth-year nursing students at a Spanish public university, the criteria that students used to choose a topic and students’ degree of satisfaction after completing the Bachelor’s thesis.DesignQuantitative study.MethodsWe examined 420 Bachelor’s theses carried out from 2013 to 2018 and conducted an online survey among fourth-year students in the 2017–18 and 2018–19 academic years (81 completed questionnaires).ResultsThe Bachelor’s thesis took the form of a research proposal. The most frequent proposal type was a qualitative hospital-based study whose objective was to understand the experiences of adult or adolescent patients, close family members, or nurses. Students chose topics for personal reasons. Most participants reported feeling satisfied with the knowledge and skills acquired.ConclusionsStudents completing a Bachelor’s thesis in the form of a research proposal have the potential to transfer their research skills to their nursing practice.  相似文献   
4.
5.
Barrett's esophagus (BE) is the precursor to esophageal adenocarcinoma (EAC). Progression to cancer typically occurs in a stepwise fashion through worsening dysplasia and ultimately, invasive neoplasia. Established EAC with deep involvement of the esophageal wall and/or metastatic disease is invariably associated with poor long-term survival rates. This guides the rationale of surveillance of Barrett’s in an attempt to treat lesions at an earlier, and potentially curative stage. The last two decades have seen a paradigm shift in management of Barrett’s with rapid expansion in the role of endoscopic eradication therapy (EET) for management of dysplastic and early neoplastic BE, and there have been substantial changes to international consensus guidelines for management of early BE based on evolving evidence. This review aims to assist the physician in the therapeutic decision-making process with patients by comprehensive review and summary of literature surrounding natural history of Barrett’s by histological stage, and the effectiveness of interventions in attenuating the risk posed by its natural history. Key findings were as follows. Non-dysplastic Barrett’s is associated with extremely low risk of progression, and interventions cannot be justified. The annual risk of cancer progression in low grade dysplasia is between 1%-3%; EET can be offered though evidence for its benefit remains confined to highly select settings. High-grade dysplasia progresses to cancer in 5%-10% per year; EET is similarly effective to and less morbid than surgery and should be routinely performed for this indication. Risk of nodal metastases in intramucosal cancer is 2%-4%, which is comparable to operative mortality rate, so EET is usually preferred. Submucosal cancer is associated with nodal metastases in 14%-41% hence surgery remains standard of care, except for select situations.  相似文献   
6.
7.
8.
9.
ABSTRACT

This project examined 55 picture books featuring transgender, gender expansive or genderqueer protagonists or narrators published between 2008 and 2018. The purpose of the study was to determine how this genre of children’s literature supports and challenges four gender assumptions: the gender binary, gender essentialism, sex/gender congruency and gender stability. Additionally, this critical analysis explored misgendering within this genre and themes of social rejection and acceptance. Protagonists and narrators were permitted a degree of gender nonconformity, however, the majority of picture books missed opportunities for a more complete exploration of gender possibilities.  相似文献   
10.
Background: Gait disorders are common in Parkinson’s disease patients who respond poorly to dopaminergic treatment. Blockade of adenosine A2A receptors is expected to improve gait disorders. Istradefylline is a first-in-class selective adenosine A2A receptor antagonist with benefits for motor complications associated with Parkinson’s disease.

Research design and methods: This multicenter, open-label, single-group, prospective interventional study evaluated changes in total gait-related scores of the Part II/III Movement Disorder Society-Unified Parkinson’s Disease Rating Scale (MDS-UPDRS) and Freezing of Gait Questionnaire (FOG-Q) in 31 Parkinson’s disease patients treated with istradefylline. Gait analysis by portable gait rhythmogram was performed.

Results: MDS-UPDRS Part III gait-related total scores significantly decreased at Weeks 4–12 from baseline with significant improvements in gait, freezing of gait, and postural stability. Significant decreases in MDS-UPDRS Part II total scores and individual item scores at Week 12 indicated improved daily living activities. At Week 12, there were significant improvements in FOG-Q, new FOG-Q, and overall movement per 48 h measured by portable gait rhythmogram. Adverse events occurred in 7/31 patients.

Conclusions: Istradefylline improved gait disorders in Parkinson’s disease patients complicated with freezing of gait, improving their quality of life. No unexpected adverse drug reactions were identified.

Trial registration: UMIN-CTR (UMIN000020288).  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号